Current and future regulations with respect to aviation fuel compositions include a no-lead requirement. Aviation fuel compositions therefore, are challenged to include components that replace the positive performance features that are a result from the incorporation of lead in aviation fuels. These challenges include meeting the rating number octane requirements of an aviation fuel composition and managing engine deposits that result from the combustion of new formulations of aviation fuels, including but not limited to manganese-containing additives. Unfortunately, the solution for some of these performance specifications can cause problems with respect to other performance specifications. The unique aviation fuel requirements present these previously unsolved challenges.